Something I find strange with his game, is that the AI is nuking units on the battleground. I have never seen the AI use nukes against units, they waste them on my SDI defense.
I'm not sure if they are. A lot of the

ed locations look like old city sites to me. But Lycerius does say he had stacks of units in the open that got

ed.
I think this may have happened to me once years ago, but I can't be sure. I seem to recall a situation in which I had a mountain fortress on an ithmus, heavily garrisoned with defensive units and arty, that took a

hit once. But I can't remember what version of Civ I was playing at the time.
Another possibility is that he's referring to the AI

ing a city that he had just captured that was surrounded by units stranded at the end of the turn. Alternatively, he could be referring to stacks of units getting

ed while assembled inside a city.
Anyway, this is something I'm currently concerned about. I'm on turn 34 of the scenario right now and I've just finished off the Vikings. I have about 100 units I'm transferring to the Eastern front to liberate the Americans from their religious oppression. Since I'm concerned about a random

ing, I'm keeping them disperserd along the railroads at the moment. Plus it's easier to keep track of them that way. And it looks cool.
One factor I've thought about is that the Celts' diplomatic reputation is "atrocious," so maybe that factors into the AIs willingness to use

s. Also, I always build a few

s and just keep them around without using them. This always inhibits the AI from using them. I've never played a game where my reputation was atrocious, with both sides slinging nukes, with large stacks of units in the open, and no nukes currently in my inventory. Perhaps
all these factors added up will cause the AI to

units in the open.